Non-isothermal pore change model predicting CO2 adsorption onto consolidated activated carbon. (October 2021)

• Record Type: Journal Article
• Authors: Berdenova, Bakytnur; Pal, Animesh; Saha, Bidyut Baran; Kaltayev, Aidarkhan
• Is Part Of: International journal of heat and mass transfer. Volume 177(2021)
• Publication Date: 2021-10
• Subjects: Activated carbon -- CO2 adsorption -- Consolidated adsorbent -- Knudsen diffusion -- Non-isothermal model; Heat -- Transmission -- Periodicals; Mass transfer -- Periodicals; Chaleur -- Transmission -- Périodiques; Transfert de masse -- Périodiques; Electronic journals; 621.4022
• DOI: 10.1016/j.ijheatmasstransfer.2021.121480
• Languages: English
• ISSNs: 0017-9310

Abstract

Highlights: Mathematical model for gas adsorption onto consolidated activated carbon is proposed. Validation of the proposed non-isothermal pore change model is performed. Dynamics curves for key parameters were constructed. Effective Knudsen diffusion coefficient for the working pair is evaluated. Adsorption rate coefficient is evaluated. Abstract: Accurate simulation and detailed description of the dynamics of the adsorption process play a significant role in forecasting the performance of new materials when used in various adsorption systems, like cooling/heating. The activated carbon (AC) consolidation allows improving the heat transfer rate inside the adsorption/desorption bed and compacting the systems. There are numerous mathematical models in literature for gas adsorption onto granular AC. But for consolidated AC, because of the absence of macropores, most assumptions that work well for granular AC may lead to significant discrepancies. Therefore, the present research proposes a new mathematical model for gas (CO2 ) adsorption onto consolidated adsorbent, a non-isothermal pore change model. The model takes into account the porosity and permeability changes due to the adsorption. The validation of the developed model is performed via comparison with the results obtained experimentally and numerically using an isothermal model. The effective Knudsen diffusion coefficient for the working pair is evaluated from porosity data. The rate of adsorption or mass transfer coefficient is estimated using the van't Hoff plot. The study results could be applied in the development of waste heat-driven cooling systems employing consolidated composite material as the adsorbent. The proposed mathematical model is also applicable for many other working pairs. Graphical Abstract: Image, graphical abstract